classic motorcycle forum

Motorcycle Discussions => British Bikes => Topic started by: Grandadsariel on December 20, 2011, 07:37:46 AM

Title: Ariel Red Hunter 1946 Smiths Speedo
Post by: Grandadsariel on December 20, 2011, 07:37:46 AM

Hello,
I am trying to find a speedo for the vintage bike I have seen these ones in the USA.Can anybody tell me if these will fit the Ariel,I am unable to measure mine as I will be away for some months and desperate to find one.

Smiths diameter across the bezel is 3 1/4" = 85.42mm, housing diameter = 3 1/8" = 80mm, with a depth of 3 1/2" = 90mm. Uses standard square inner cable, with the larger 9/16" = 17.82mm outer cable nut. Bracket to hold gauge inside is included, as is a pilot bulb and socket


Ebay link      My World: valtermotousa( 3042)

Thanks mark

Title: Re: Ariel Red Hunter 1946 Smiths Speedo
Post by: twolitre on December 20, 2011, 11:50:35 AM

Apart from physical dimensions, mounting and appearance, speedometers vary in the number of turns per mile (tpi) required due to variations in drive ratio and wheel and tyre size.
Some Smiths and Jeager speedos have the tpi in small numbers on the dial.

Title: Re: Ariel Red Hunter 1946 Smiths Speedo
Post by: R on December 21, 2011, 01:25:36 AM

Speedos also vary in whether they are calibrated in mph or km/hr.
And even clockwise or anticlock in some cases...

In the immediate postwar era, 80mph would have been common and 120 mph probably optional, as a clockwise chronometric type (the needle ticks upwards like a clock, not a smooth sweep like the 1960s magnetic type).

Almost all speedos will work on any bike, whether they read correctly is something else.  A speedo expert can generally rework the internals so any speedo will read and show whatever you want.

Someone somewhere will have the Smiths chart that says what numbers your speedo would have had originally - actually finding exactly that one is something else.

Hopethishelps.

Title: Re: Ariel Red Hunter 1946 Smiths Speedo
Post by: Grandadsariel on December 21, 2011, 08:51:39 PM

Thanks everybody for your replies,the speedo reading on the original is 100mph.

The speedo is the only problem I have to get it licensed,the cops don't test ride the bike they just put the stand down and run it with the wheel of the ground to make sure it works.

If the speedo fits in the tank and cable fits it will do for now,or I mite be lucky and it is spot on.

Are those sizes rite for the tank sizes

Mark

Title: Re: Ariel Red Hunter 1946 Smiths Speedo
Post by: wetdog on December 21, 2011, 08:57:39 PM

where are you ? what do they do if the speedo is driven off the front wheel ?

Title: Re: Ariel Red Hunter 1946 Smiths Speedo
Post by: Grandadsariel on December 21, 2011, 09:02:41 PM

Perth Australia

He said he was not going to ride it so just put the stand up

I suppose depending on the bike and inspector which way they test

Mark